/* $OpenBSD: wdt.c,v 1.21 2012/10/17 22:32:01 deraadt Exp $ */ /*- * Copyright (c) 1998,1999 Alex Nash * All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. * */ #include #include #include #include #include #include #include #include #include struct wdt_softc { /* wdt_dev must be the first item in the struct */ struct device sc_dev; /* feature set: 0 = none 1 = temp, buzzer, etc. */ int sc_features; /* device access through bus space */ bus_space_tag_t sc_iot; bus_space_handle_t sc_ioh; }; int wdt_probe(struct device *, void *, void *); void wdt_attach(struct device *, struct device *, void *); int wdt_is501(struct wdt_softc *); void wdt_8254_count(struct wdt_softc *, int, u_int16_t); void wdt_8254_mode(struct wdt_softc *, int, int); int wdt_set_timeout(void *, int); void wdt_init_timer(struct wdt_softc *); void wdt_buzzer_off(struct wdt_softc *); void wdt_timer_disable(struct wdt_softc *); void wdt_buzzer_enable(struct wdt_softc *); struct cfattach wdt_ca = { sizeof(struct wdt_softc), wdt_probe, wdt_attach }; struct cfdriver wdt_cd = { NULL, "wdt", DV_DULL }; const struct pci_matchid wdt_devices[] = { { PCI_VENDOR_INDCOMPSRC, PCI_PRODUCT_INDCOMPSRC_WDT50x } }; /* * 8254 counter mappings */ #define WDT_8254_TC_LO 0 /* low 16 bits of timeout counter */ #define WDT_8254_TC_HI 1 /* high 16 bits of timeout counter */ #define WDT_8254_BUZZER 2 /* * WDT500/501 ports */ #define WDT_8254_BASE 0 #define WDT_8254_CTL (WDT_8254_BASE + 3) #define WDT_DISABLE_TIMER 7 #define WDT_ENABLE_TIMER 7 /* * WDT501 specific ports */ #define WDT_STATUS_REG 4 #define WDT_START_BUZZER 4 #define WDT_TEMPERATURE 5 #define WDT_STOP_BUZZER 5 int wdt_probe(struct device *parent, void *match, void *aux) { return (pci_matchbyid((struct pci_attach_args *)aux, wdt_devices, nitems(wdt_devices))); } void wdt_attach(struct device *parent, struct device *self, void *aux) { struct wdt_softc *wdt = (struct wdt_softc *)self; struct pci_attach_args *const pa = (struct pci_attach_args *)aux; bus_size_t iosize; /* retrieve the I/O region (BAR2) */ if (pci_mapreg_map(pa, 0x18, PCI_MAPREG_TYPE_IO, 0, &wdt->sc_iot, &wdt->sc_ioh, NULL, &iosize, 0) != 0) { printf("%s: couldn't find PCI I/O region\n", wdt->sc_dev.dv_xname); return; } /* sanity check I/O size */ if (iosize != (bus_size_t)16) { printf("%s: invalid I/O region size\n", wdt->sc_dev.dv_xname); return; } /* initialize the watchdog timer structure */ /* check the feature set available */ if (wdt_is501(wdt)) wdt->sc_features = 1; else wdt->sc_features = 0; if (wdt->sc_features) { /* * turn off the buzzer, it may have been activated * by a previous timeout */ wdt_buzzer_off(wdt); wdt_buzzer_enable(wdt); } /* initialize the timer modes and the lower 16-bit counter */ wdt_init_timer(wdt); /* * ensure that the watchdog is disabled */ wdt_timer_disable(wdt); /* * register with the watchdog framework */ wdog_register(wdt_set_timeout, wdt); } /* * wdt_is501 * * Returns non-zero if the card is a 501 model. */ int wdt_is501(struct wdt_softc *wdt) { /* * It makes too much sense to detect the card type * by the device ID, so we have to resort to testing * the presence of a register to determine the type. */ int v = bus_space_read_1(wdt->sc_iot, wdt->sc_ioh, WDT_TEMPERATURE); /* XXX may not be reliable */ if (v == 0 || v == 0xFF) return(0); return(1); } /* * wdt_8254_count * * Loads the specified counter with the 16-bit value 'v'. */ void wdt_8254_count(struct wdt_softc *wdt, int counter, u_int16_t v) { bus_space_write_1(wdt->sc_iot, wdt->sc_ioh, WDT_8254_BASE + counter, v & 0xFF); bus_space_write_1(wdt->sc_iot, wdt->sc_ioh, WDT_8254_BASE + counter, v >> 8); } /* * wdt_8254_mode * * Sets the mode of the specified counter. */ void wdt_8254_mode(struct wdt_softc *wdt, int counter, int mode) { bus_space_write_1(wdt->sc_iot, wdt->sc_ioh, WDT_8254_CTL, (counter << 6) | 0x30 | (mode << 1)); } /* * wdt_set_timeout * * Load the watchdog timer with the specified number of seconds. * Clamp seconds to be in the interval [2; 1800]. */ int wdt_set_timeout(void *self, int seconds) { struct wdt_softc *wdt = (struct wdt_softc *)self; u_int16_t v; int s; s = splclock(); wdt_timer_disable(wdt); if (seconds == 0) { splx(s); return (0); } else if (seconds < 2) seconds = 2; else if (seconds > 1800) seconds = 1800; /* 8254 has been programmed with a 2ms period */ v = (u_int16_t)seconds * 50; /* load the new timeout count */ wdt_8254_count(wdt, WDT_8254_TC_HI, v); /* enable the timer */ bus_space_write_1(wdt->sc_iot, wdt->sc_ioh, WDT_ENABLE_TIMER, 0); splx(s); return (seconds); } /* * wdt_timer_disable * * Disables the watchdog timer and cancels the scheduled (if any) * kernel timeout. */ void wdt_timer_disable(struct wdt_softc *wdt) { (void)bus_space_read_1(wdt->sc_iot, wdt->sc_ioh, WDT_DISABLE_TIMER); } /* * wdt_init_timer * * Configure the modes for the watchdog counters and initialize * the low 16-bits of the watchdog counter to have a period of * approximately 1/50th of a second. */ void wdt_init_timer(struct wdt_softc *wdt) { wdt_8254_mode(wdt, WDT_8254_TC_LO, 3); wdt_8254_mode(wdt, WDT_8254_TC_HI, 2); wdt_8254_count(wdt, WDT_8254_TC_LO, 41666); } /******************************************************************* * WDT501 specific functions *******************************************************************/ /* * wdt_buzzer_off * * Turns the buzzer off. */ void wdt_buzzer_off(struct wdt_softc *wdt) { bus_space_write_1(wdt->sc_iot, wdt->sc_ioh, WDT_STOP_BUZZER, 0); } #ifndef WDT_DISABLE_BUZZER /* * wdt_buzzer_enable * * Enables the buzzer when the watchdog counter expires. */ void wdt_buzzer_enable(struct wdt_softc *wdt) { bus_space_write_1(wdt->sc_iot, wdt->sc_ioh, WDT_8254_BUZZER, 1); wdt_8254_mode(wdt, WDT_8254_BUZZER, 1); } #else /* * wdt_buzzer_disable * * Disables the buzzer from sounding when the watchdog counter * expires. */ void wdt_buzzer_disable(struct wdt_softc *wdt) { wdt_8254_mode(wdt, WDT_8254_BUZZER, 0); } #endif